Precision farming, agriculture "close up"
Electronic and computer systems for the scientific management of agricultural work parameters represent the new technological frontier, which farmers in all the most developed countries are increasingly interested in. In addition to the advantages in strictly agronomic terms, precision farming systems allow businesses to produce at lower cost, with the ability to cope with those crises of profitability that nowadays regularly affect the global primary sector
Increasing production and productivity to meet an increasing and demanding population, cost reductions, and greater respect for the environment; these are the goals that the primary sector set itself today to face the social, economic and environmental challenges at the heart of an international debate. To illustrate a representative snapshot of the sector, it is necessary to add that many of today’s farm crops are unable to provide a fair income to farmers due to factors that negatively impact the profit margins of farms. The continuous increase in the purchase price of technical means (diesel, fertilizers, herbicides, etc.) is offset by a sharp fall in the market value of the product, also owing to the increasing competitiveness of emerging economies’ production and the gradual changes adopted by the EU with regard to income support measures.
Innovative processes can, however, help farmers combine profitability and sustainability by reducing energy and water resources consumption and the use of fertilizers and pesticides. Research applied to agriculture has made great strides in recent years. The implementation of the most advanced technological innovations enables the development of low environmental impact, low-cost farming systems through the use of tools to automatically control the distribution of all production factors, with particular regard to potential pollutants (fertilizers and pesticides). This also allows the farm managers to implement forms of proactive process management, with the resulting increase in labour productivity and reduction of production costs, in order to achieve sustainable agriculture in environmental and economic terms.
This approach is theorized and implemented under the name of Precision Farming (PF).
Developed in the early 1990s in the United States of America, Precision Farming, also known as Site Specific Farming Management, consists in the application of technologies, principles and strategies for spatial and temporal management of the variability associated with aspects of agricultural production in relation to the actual needs of the land parcel (Pierce and Nowak, 1999).
It can therefore be understood as a form of advanced agriculture, devoted to the use of techniques and technologies aimed at the variable application of crop inputs to the soil. This is carried out on the basis of the actual need of the crop and the chemical-physical and biological properties of the soil, in order to pursue agronomic benefits, increasing crop performance by streamlining inputs and reducing environmental and crop costs (Godwin, 2003).
An advanced form of agriculture that nevertheless bases its very existence in the past, PF, as a concept, is not a new idea. Just a few decades ago, the farmer examined his fields in person, traversing them long and wide several times throughout the year. He was thus able to observe the variability within the plot and intervene from time to time with targeted solutions, distributing higher fertilizer doses where growth was lower or increasing the dose of seeds where there was less sprouting.
This knowledge depended on his memory, kept up to date through direct observation. Such an approach has become difficult to follow given the increase in the size of farms and the growing use of subcontracting. The farm fields have become larger and more numerous, and the option for the farmer to evaluate and manage individual variability situations has gradually shrunk.
In agriculture, any given plot is characterized by a certain variability affecting several parameters related to the nature of the soil itself. The challenge has always been to identify those parameters that have adverse effects on crop yield, in order to intervene on productivity-limiting factors with effective inputs (higher doses of fertilizer, greater use of irrigation, etc.). From these considerations, it is possible to perceive the importance of dividing fields into homogeneous parcels to be managed in a uniform way, different from the rest of the plot, in order to increase the yield and thus obtain a greater economic return.
Over the years, however, the size of the parcels has gradually increased, with interventions being calibrated on average values, with the assumption that these were representative of the whole area, mistakenly considered homogeneous. With the implementation of the first systems for performance monitoring and yield measurement by creating special maps, these parameters have been shown to vary considerably even within a single plot. This awareness has essentially stimulated interest in all those technologies that allow to measure the variability present in the fields, to identify those areas to be treated differently and apply solutions to them that generate increases in yields.
PF can therefore be understood as a new farm management approach whose implementation goes through three main phases: the collection and recording of data to determine the variability of the field being studied, followed by a decision phase where the data is interpreted, enabling the definition of the choices and strategies to be adopted.
There are several techniques for data collection, and the one that gave impetus to PF is the use of the Global Positioning System (GPS), with makes it possible to identify and record the position of any receiver on the Earth’s surface with the aid of a system of satellites orbiting around the Earth. The GPS system in agriculture can find the most varied applications, with the navigation system being perhaps the most well-known. This is an electronic driving system that uses satellite receivers to indicate to the operator of a machine the optimal path to follow in the field by means of light or acoustic signals (guiding bar) or to drive the tractor independently along a straight path (semi-automatic guidance).
In addition to the spatial references (GPS), the modes of data acquisition geographical information systems (GISs) can be used, through which it is possible to combine geographical data with other data to generate summary technical maps. Meanwhile, remote sensing uses information obtained from aerial or satellite platforms that are able to exploit electromagnetic radiation at one or more wavelengths. Among other things, these provide information on the state of health of the crop, its progress during the production cycle, the product ripening phase and optimum harvest period. Finally, the use of sensors on specific machines, such as combine harvesters, enables an instant measurement of the quantity and quality of seeds at every point of the plot, with the resulting ability to prepare precise production maps.
Once the variability of the field is established and its size is quantified, the implementation of PF techniques requires a careful and cautious decision-making phase. Besides processing the collected data, this phase consists of assessing the dynamics and the mutual influences of soil, climate, genetics and cultivation practices. Technology provides the solutions: it is possible to use simulations through the development of computerized models that help to forecast the effectiveness of cultivation practices with different management approaches for a given soil, in a precise climatic zone, and with an established cultivar.
Having identified the strategy to be implemented, the operator will have to use specific equipment. It will therefore be necessary to adapt the available fleet with tools and systems developed for PF. And so, thanks to ISOBUS technology, veritable on-board computers enter the cab, enabling them to interact with the machines, to distribute inputs such as seeds, fertilizers, pesticides, etc. in a differentiated and streamlined way, and to support the farmer in carrying out the needed operations, alleviating the more complex and tiring ones.
Some machines equipped with GPS will be able to adjust the delivered amount of a specific treatment through the information provided in the maps obtained previously, modulating their operation depending on their location on the plot. Other machines will use sensors to detect in real time the parameters related to the yield of the crop that will be used as indicators for the distribution of the various inputs.
From all the above, we can imagine the impact that PF can have on global agriculture. The economic benefits derive from streamlining the use of various crop factors and from a management that is able to anticipate emergencies, and environmental benefits result from the targeted use of chemicals, with a positive impact on quality of water, soil and air; PF makes it easier to implement conservative soil processing techniques, such as non-inversion of layers, minimal processing and non-processing, which have the advantage of reducing erosion, increasing soil fertility, reducing CO2 emissions and optimizing the use of water, contributing to the mitigation of climate overheating due to anthropic activity and excessive use of land.
PF is also suitable for all other forms of agriculture, such as organic farming, multifunctional farming, crops for the production of biofuels, subsistence farming, and so on, because it enhances and rationalizes their goals.
In Italy, today only 1% of the cultivated arable land sees the use of PF means and technologies, while the Ministry for Food and Forestry Policies aims to reach 10% by 2021. The technologies exist, farmers are responsible for implementing them.
